Apollo 12 Mission

Surface Operations Overview

The Apollo 12 mission provided the first opportunity to study the Moon extensively within a
radius of 0.5 kilometers of the landing site. Lunar surface activities were performed essentially
as planned within the allotted time periods. Three hours after landing, the crew began
preparations for egress and the first traverse of the lunar surface. During the two
extravehicular activity periods, a total duration of 7.5 hours, the astronauts were given very
specific tasks to complete. Among these were to collect lunar samples, to deploy several experiments, and to examine and photograph the lunar surface. The following map of the landing
area shows where these activities took place.

The first EVA began at 6:32 a.m. EST on November 19, 1969. A color television camera mounted on the Modularized Equipment Stowage Assembly on the Lunar Module descent stage provided live television coverage of the descent of both astronauts to the lunar surface. During this EVA, the crew collected samples in the vicinity of the lunar module, including a core-tube sample of
subsurface material, erected the Solar Wind Composition foil collector, and deployed the Apollo
Lunar Surface Experiments Package. The EVA ended at 10:28 a.m. EST after 3 hours and 56
minutes.

The Apollo 12 Lunar Module

Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 mission, works at the Modular Equipment Stowage Assembly on the Apollo 12 LM during the mission's first extravehicular activity on November 19, 1969.

Collecting the Contingency Sample

The contingency sample was taken on and near the southeast rim of a 6-meter-diameter crater
approximately 15 meters northwest of the Lunar Module. Six scoops were taken, amounting to
about 1.9 kilograms of material. The contingency sample was collected to ensure that some
material from this landing site would be returned to Earth in the event that an emergency
required a rapid, unscheduled end to the EVA.

Activities at the Lunar Module Site

The erectable S-band antenna was easy to deploy on its tripod but difficult to align. Although one-man deployment was satisfactory, it took both astronauts to align the antenna.

Deployment of the Televison Camera

The TV camera was removed from the LM for deployment on the surface. However, during the
transfer, the camera was accidentally pointed at the Sun or the Sun's reflection on the descent
stage and the vision tube apparently burned out. This ended the TV coverage of the lunar surface
activities.

Placing the Flag on the Lunar Surface

The TV camera was removed from the LM for deployment on the surface. However, during the
transfer, the camera was accidentally pointed at the Sun or the Sun's reflection on the descent
stage and the vision tube apparently burned out. This ended the TV coverage of the lunar surface
activities.

Deployment of the Solar Wind Composition Experiment

The Sun continually emits a flux of electrically charged particles into space. This is termed
the solar wind. The Earth's magnetic field prevents these charged particles from reaching the
Earth's surface, although in the Earth's polar regions, these particles can reach the upper part
of the atmosphere, causing auroras. The Moon is outside the Earth's magnetic field for most of
each month and has a negligible atmosphere, allowing solar wind particles to reach the Moon's
surface. Two different experiments, the Solar Wind Composition Experiment and the Solar Wind Spectrometer, were deployed on the Moon to
study the solar wind.

The Solar Wind Composition Experiment was performed on Apollo 11, 12, 14, 15, and 16. It
consisted of an aluminum foil sheet, 1.4 meters by 0.3 meters, that was deployed on a pole facing
the Sun. On Apollo 16, a platinum sheet was also used. This foil was exposed to the Sun for
periods ranging from 77 minutes on Apollo 11 to 45 hours on Apollo 16, allowing solar wind
particles to embed themselves into the foil. The foil was then returned to Earth for laboratory
analysis. This allowed the chemical composition of the embedded solar wind to be determined more
accurately than would be possible if the measurement were made using remotely controlled
instruments on the Moon, but limited the periods at which observations could be made. The
isotopes of the light noble gases were measured, including helium-3, helium-4, neon-20, neon-21,
neon-22, and argon-36. Some variation in the composition of the solar wind was observed in the
measurements from the different missions. These variations were correlated with variations in
the intensity of the solar wind as determined from magnetic field measurements.

The Solar Wind Composition experiment on Apollo 12 was the same as the experiment flown on Apollo 11. The experiment was deployed on the lunar
surface and was exposed to the solar wind for 18 hours and 42 minutes. Afterward, the foil was
removed and placed in a Teflon bag and returned to Earth for analysis.

Unloading the ALSEPIn this photograph, the astronauts are shown removing the ALSEP from their stowage areas on
the descent stage of the LM. The ALSEP is in two subpackages that are folded up or collapsed
for more compact storage.

Transporting the ALSEPAstronaut Alan L. Bean, lunar module pilot, carries the two subpackages of the ALSEP. The
subpackages have been left in their collapsed form for easier handling.

Setting up the ALSEPCommander Charles Conrad Jr. aligns the antenna on the central station for the ALSEP. The
ALSEP's Lunar Surface Magnetometer is in the foreground. In the center background near Conrad
are other ALSEP components.

Additional Sampling

The selected sample was collected in an area northwest of the LM in the vicinity of Middle
Cresent Crater. Samples were taken in the vicinity of the ALSEP and on and near two mounds
approximately 120 and 160 meters northwest of the LM. One core tube was also driven near the
LM. In all, about 14.8 kilograms of material was collected in about 1.25 hours.

Other EVA Activities

In addition to the activities listed above, the astronauts took many photographs, including
some panoramic sequences. Also, at the request of geologists on Earth, the crew made a traverse
to a 300-meter-diameter crater after completing the ALSEP deployment.

Second Extravehicular Activity

The second extravehicular activity period began on November 19 at 10:54 p.m. EST. The major
activity of this EVA was the geology traverse, which covered a distance of approximately 4300
feet. The EVA lasted 3 hours and 50 minutes, ending at 2:44 a.m. EST on November 20.

The Geologic Traverse

The contingency sample was taken on and near the southeast rim of a 6-meter-diameter crater
approximately 15 meters northwest of the Lunar Module. Six scoops were taken, amounting to
about 1.9 kilograms of material. The contingency sample was collected to ensure that some
material from this landing site would be returned to Earth in the event that an emergency
required a rapid, unscheduled end to the EVA.

The documented sampling was performed during this traverse and consisted of about 17.6
kilograms of rocks, soil, and core samples. The traverse followed a planned course and samples
were collected primarily from the crater rims.

Head Crater
Samples were taken at four locations around the rim of Head Crater: one on the north-northeast
side, two on the north side, and one more on the north-northwest side of the rim. Samples taken
at this site included five rocks and two soil samples.

Bench Crater
This crater was about 280 meters southwest of the LM. Samples were taken at three locations
along the northwest rim. A total of three soil samples and six rock samples were collected.

Sharp Crater
At this site, a lunar environment sample and a gas analysis sample were taken. These samples
were sealed in special containers separate from the other lunar samples. A core tube sample was
also obtained. Sharp Crater was about 400 meters southwest of the lunar module (LM).

Halo Crater
A double core tube sample was taken on the rim of a 10-meter-diameter crater south of Halo Crater.
Additional samples were taken at three other locations within 50 meters of this crater.

Surveyor Crater
A total of 10 rocks and two soil samples were collected on or near the rim of this crater. Four
sample sites were located at the Surveyor III lander itself. One location was just outside the
southernmost point on the rim and another was at Block Crater just inside the northeast rim of
the crater.

Visit to Surveyor III Site

The Surveyor III spacecraft was launched in April 1967
and was exposed on the lunar surface for 31 months before the Apollo 12 mission. The Apollo 12 Lunar Module landed approximately 160 meters from the Surveyor 3 spacecraft. The crew retrieved
several pieces of the Surveyor, including the TV camera and associated electrical cables, the
sample scoop, and two pieces of aluminum tubing. These items were returned to Earth and analyzed
to determine how they were affected by exposure to the lunar environment.

A number of microscopic craters were observed on the returned pieces. Some were probably the
result of micrometeorite bombardment of the Moon. Many of these craters were on the side of the
Surveyor facing the Lunar Module. It is likely that these are the result of a sand-blasting
effect from dust that was blown away from the Apollo landing site by rocket exhaust. Some
darkening of painted surfaces due to the effects of solar radiation was also observed. Several
nuts, bolts, and screws were disassembled after being returned to Earth, and none were found to
have become cold-welded by their exposure to space.

A particularly important aspect of the Surveyor 3 analysis was the search for living material
on the spacecraft. Surveyor was not sterilized prior to launch, and scientists wanted to know if
terrestrial microorganisms had survived for two and a half years in space. One research group
found a small amount of the bacteria Streptococcus mitis in a piece of foam from inside
the TV camera. They believed that these bacteria had survived in this location since before
launch. They only found evidence for living material in one of 33 samples from various parts of Surveyor that they cultured. Another research group found no evidence of life inside a section of
electrical cable. Some people associated with the curation of the Surveyor 3 materials have
suggested that the one positive detection of life may be the result of accidental contamination
of the material after it was returned to Earth.

Other EVA Activities

Apollo Lunar Surface Close-up Camera PhotographyThis activity suffered somewhat due to lack of time at the end of the second EVA. The areas
photographed were mostly around the LM. The camera performed satisfactorily, except that the
film counter did not work. A total of 15 stereoscopic photo pairs of excellent quality were
taken.

End of the Apollo 12 MissionA close-up view of a replica of the plaque the Apollo 12 astronauts left on the Moon in
commemoration of their flight. The plaque was attached to the ladder on the landing gear strut
on the descent stage of the Apollo 12 LM.